1 |
/* Copyright (c) 1998 Silicon Graphics, Inc. */ |
2 |
|
3 |
/* SCCSid "$SunId$ SGI" */ |
4 |
|
5 |
/* |
6 |
* sm_stree.h - header file for spherical quadtree code: |
7 |
* |
8 |
*/ |
9 |
|
10 |
|
11 |
#define ST_NUM_ROOT_NODES 8 |
12 |
|
13 |
/* The base is an octahedron: Each face contains a planar quadtree. At |
14 |
the root level, the "top" (positive y) four faces, and bottom four faces |
15 |
are stored together:forming two root quadtree nodes |
16 |
*/ |
17 |
|
18 |
typedef struct _STREE { |
19 |
QUADTREE root[2]; /* root[0]= top four faces, root[1]=bottom 4 faces*/ |
20 |
FVECT center; /* sphere center */ |
21 |
FVECT base[6]; /* 6 vertices on sphere that define base octahedron: |
22 |
in canonical form: origin(0,0,0) points (1,0,0), |
23 |
(0,1,0),(0,0,1),(-1,0,0),(0,-1,0),(0,0,-1) */ |
24 |
FPEQ fplane[8]; /* Face plane equations */ |
25 |
|
26 |
FVECT enorms[8][3]; /* Edge normals: For plane through edge and origin*/ |
27 |
}STREE; |
28 |
|
29 |
|
30 |
#define ST_BASEI(n) ((n)>>2) /* root index: top or bottom */ |
31 |
#define ST_INDEX(n) ((n) & 0x3) /* which child in root */ |
32 |
#define ST_ROOT(s,i) ((s)->root[ST_BASEI(i)]) /* top or bottom root*/ |
33 |
#define ST_ROOT_PTR(s,i) (&ST_ROOT(s,i)) /* ptr to top(0)/bottom(1)root*/ |
34 |
#define ST_TOP_ROOT(s) ((s)->root[0]) /* top root (y>0)*/ |
35 |
#define ST_BOTTOM_ROOT(s) ((s)->root[1]) /* bottom root (y <= 0)*/ |
36 |
#define ST_TOP_ROOT_PTR(s) (&ST_TOP_ROOT(s)) /* ptr to top root */ |
37 |
#define ST_BOTTOM_ROOT_PTR(s) (&ST_BOTTOM_ROOT(s)) /* ptr to bottom root*/ |
38 |
#define ST_NTH_ROOT(s,n) QT_NTH_CHILD(ST_ROOT(s,n),ST_INDEX(n)) |
39 |
#define ST_NTH_ROOT_PTR(s,n) QT_NTH_CHILD_PTR(ST_ROOT(s,n),ST_INDEX(n)) |
40 |
#define ST_CLEAR_ROOT(st) (ST_TOP_ROOT(st)=EMPTY,ST_BOTTOM_ROOT(st)=EMPTY) |
41 |
#define ST_INIT_ROOT(st) (QT_CLEAR_CHILDREN(ST_TOP_ROOT(st)), \ |
42 |
QT_CLEAR_CHILDREN(ST_BOTTOM_ROOT(st))) |
43 |
#define ST_BASE(s) ((s)->base) |
44 |
#define ST_NTH_BASE(s,n) ((s)->base[(n)]) |
45 |
#define ST_NTH_V(s,n,i) ST_NTH_BASE(s,stBase_verts[(n)][(i)]) |
46 |
#define ST_SET_NTH_BASE(s,n,b) VCOPY(ST_NTH_BASE(s,n),b) |
47 |
#define ST_SET_BASE(s,b) (VCOPY(ST_NTH_BASE(s,0),(b)[0]), \ |
48 |
VCOPY(ST_NTH_BASE(s,1),(b)[1]), \ |
49 |
VCOPY(ST_NTH_BASE(s,2),(b)[2]), \ |
50 |
VCOPY(ST_NTH_BASE(s,3),(b)[3]), \ |
51 |
VCOPY(ST_NTH_BASE(s,4),(b)[4]), \ |
52 |
VCOPY(ST_NTH_BASE(s,5),(b)[5])) |
53 |
|
54 |
#define ST_CENTER(s) ((s)->center) |
55 |
#define ST_SET_CENTER(s,b) VCOPY(ST_CENTER(s),b) |
56 |
|
57 |
#define ST_NTH_PLANE(s,i) ((s)->fplane[(i)]) |
58 |
#define ST_NTH_NORM(s,i) (ST_NTH_PLANE(s,i).n) |
59 |
#define ST_NTH_D(s,i) (ST_NTH_PLANE(s,i).d) |
60 |
#define ST_EDGE_NORM(s,i,n) ((s)->enorms[(i)][(n)]) |
61 |
|
62 |
#define ST_COORD(s,p,r) VSUB(r,p,ST_CENTER(s)) |
63 |
#define ST_CLEAR_FLAGS(s) qtClearAllFlags() |
64 |
|
65 |
/* Point location based on coordinate signs */ |
66 |
#define TST(p) ((p)>0.0?1:0) |
67 |
#define stPoint_in_root(p) stlocatetbl[TST((p)[0])<<2 | (TST((p)[1])<<1) \ |
68 |
| TST((p)[2])] |
69 |
|
70 |
/* STREE functions |
71 |
void stInit(STREE *st,FVECT center) |
72 |
Initializes an stree structure with origin 'center': |
73 |
Frees existing quadtrees hanging off of the roots |
74 |
|
75 |
STREE *stAlloc(STREE *st) |
76 |
Allocates a stree structure and creates octahedron base |
77 |
|
78 |
void stClear(STREE *st) |
79 |
Frees any existing root children and clears roots |
80 |
|
81 |
QUADTREE stPoint_locate(STREE *st,FVECT p) |
82 |
Returns quadtree leaf node containing point 'p'. |
83 |
|
84 |
int stAdd_tri(STREE *st,int id,FVECT t0,t1,t2) |
85 |
Add triangle 'id' with coordinates 't0,t1,t2' to the stree: returns |
86 |
FALSE on error, TRUE otherwise |
87 |
|
88 |
int stRemove_tri(STREE *st,int id,FVECT t0,t1,t2) |
89 |
Removes triangle 'id' with coordinates 't0,t1,t2' from stree: returns |
90 |
FALSE on error, TRUE otherwise |
91 |
|
92 |
int stTrace_ray(STREE *st,FVECT orig,dir,int (*func)(),int *arg1,*arg2) |
93 |
Trace ray 'orig-dir' through stree and apply 'func(arg1,arg2)' at each |
94 |
node that it intersects |
95 |
|
96 |
int stApply_to_tri(STREE *st,FVECT t0,t1,t2,int (*edge_func)(), |
97 |
(*tri_func)(),int arg1,*arg2) |
98 |
Visit nodes intersected by tri 't0,t1,t2'.Apply 'edge_func(arg1,arg2,arg3)', |
99 |
to those nodes intersected by edges, and interior_func to ALL nodes: |
100 |
ie some Nodes will be visited more than once |
101 |
*/ |
102 |
|
103 |
extern int stBase_verts[8][3]; |
104 |
extern STREE *stAlloc(); |
105 |
extern QUADTREE stPoint_locate(); |
106 |
|
107 |
|
108 |
|
109 |
|
110 |
|